1. Field of the Invention
The present invention relates to attachment apparatus for bicycle parts and, more particularly, to an attachment apparatus for use in attaching bicycle parts which require connections through cords to bicycles.
2. Description of the Background Art
Recently, speedometers are sometimes attached to bicycles in order to readily know travel speed and travel distance of the bicycles.
FIG. 6 is a side view showing structure of a bicycle to which such a speedometer is attached.
Referring to FIG. 6, a speedometer 30 is detachably attached to a handle 19. A front-wheel fork 32 of the bicycle is provided with a speed sensor 28 for generating one pulse signal every time a magnet 26 attached to a front-wheel spoke passes in front of speed sensor 28. Speedometer 30 and speed sensor 28 are connected through a cord 25 for transmitting generated signals therethrough.
FIG. 7 is an enlarged view of an attachment portion of speedometer 30; and FIG. 8 is a plan view viewed from the line VIII--VIII of attachment parts of FIG. 7.
Referring to FIGS. 7 and 8, an attachment part 37 of speedometer 30 comprises a ring portion A39 which is pivotal on a pin 43, and a ring portion B41. Respective ends of ring portions A39 and B41 are fastened by a screw 49. In attachment, ring portions A39 and B41 are opened to interpose handle 19 therebetween with screw 49 being detached, and screw 49 is fastened with a packing 5 fixed between handle 19 and attachment part 37. Attachment part 37 is thus firmly attached on a desired position of the handle. Ring portion B45 is provided with an engagement portion 45 to be detachably engaged with speedometer 30. On a top surface of engagement portion 45 are provided rivet contacts 47a and 47b for transmitting a signal transmitted through cord 25 from speed sensor 28, with speedometer 30 engaged with engagement portion 45.
FIG. 9 is a cross-sectional view taken along the line IX--IX of FIG. 7.
Referring to FIG. 9, a double groove 46 for engaging with speedometer 30 is provided in engagement portion 45. A recess 48 is formed in a lower surface of engagement portion 45. A base plate 53 is disposed in recess 48. Rivet contacts 47a and 47b provided on the top surface of engagement portion 45 are conducted to base plate 53 via conductors 51a and 51b, respectively. Respective core wires 29a and 29b of cord 25 are connected by soldering to respective conductors 51a and 51b projected from base plate 53. With respective core wires 29a and 29b of cord 25 connected by soldering, polyurethane resin 55 is sealed in recess 48 of engagement portion 45 in order to seal and protect the connecting portion of core wires 29a and 29b from the outside.
In the above-described conventional attachment apparatus for bicycle parts, it is necessary to provide a resin sealing such as by polyurethane resin, and hence, it takes time to manufacture such apparatus. Once the resin sealing is provided, defects occurring in base plate 53 and the connecting portion of core wires 29a and 29b can not readily be inspected or repaired. As a result, the ratio of good quality product (productivity) is decreased.